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Registros recuperados: 31
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DYNAMIC ANALYSIS WITH TIME SERIES MODELS: SIMULATION AND EMPIRICAL EVIDENCE AgEcon
Robledo, Carlos W.; Zapata, Hector O..
The performance of the FPE, AIC, HQ and SC criteria in choosing lag-length, and the effect on the impulse-response functions, are studied in a Monte Carlo simulation. The experiments include stationary, cointegrated, and mixed unit root VAR and MA cases.
Tipo: Conference Paper or Presentation Palavras-chave: Statistical selection criteria; Cointegration; Mixed unit roots; Impulse response functions; Small sample properties; Research Methods/ Statistical Methods.
Ano: 1999 URL: http://purl.umn.edu/21526
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Analysis of Expected Price Dynamics Between Fluid Milk Futures Contracts and Cash Prices for Fluid Milk AgEcon
Fortenbery, T. Randall; Cropp, Robert A.; Zapata, Hector O..
Future contracts for fluid milk began trading in late 1995 and early 1996. This paper investigates the potential use of fluid milk futures contracts as hedge vehicles for dairy producers in the Upper Midwest and California markets. This is done by developing simulated futures prices for the period 1988 to 1995. The simulated futures prices are used to estimate basis relationships between cash and futures prices for the markets considered. Results suggest that the fluid milk futures contracts could be used to reduce market price risk for producers in the Upper Midwest. Results were less conclusive for California producers.
Tipo: Journal Article Palavras-chave: Fluid milk futures; Contracts; Basis; Dairy markets; Agribusiness; Demand and Price Analysis.
Ano: 1997 URL: http://purl.umn.edu/90427
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SELECTING THE "BEST" PREDICTION MODEL: AN APPLICATION TO AGRICULTURAL COOPERATIVES AgEcon
Rambaldi, Alicia N.; Zapata, Hector O.; Christy, Ralph D..
A credit scoring function incorporating statistical selection criteria was proposed to evaluate the credit worthiness of agricultural cooperative loans in the Fifth Farm Credit District. In-sample (1981-1986) and out-of-sample (1988) prediction performance of the selected models were evaluated using rank transformation discriminant analysis, logit, and probit. Results indicate superior out-of-sample performance for the management oriented approach relative to classification of unacceptable loans, and poor performance of the rank transformation in out-of-sample prediction.
Tipo: Journal Article Palavras-chave: Agribusiness.
Ano: 1992 URL: http://purl.umn.edu/30380
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PRICE FORECASTING WITH TIME-SERIES METHODS AND NONSTATIONARY DATA: AN APPLICATION TO MONTHLY U.S. CATTLE PRICES AgEcon
Zapata, Hector O.; Garcia, Philip.
The forecasting performance of various multivariate as well as univariate ARIMA models is evaluated in the presence of nonstationarity. The results indicate the importance of identifying the characteristics of the time series by testing for types of nonstationarity. Procedures that permit model specifications consistent with the system’s dynamics provide the most accurate forecasts.
Tipo: Journal Article Palavras-chave: Demand and Price Analysis; Livestock Production/Industries.
Ano: 1990 URL: http://purl.umn.edu/32505
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A Semiparametric Approach to Estimate Engel curves using the US Micro Data AgEcon
Zapata, Hector O.; Sulgham, Anil K..
The study estimates Engel curves using cross-section data from the 2003 US consumer expenditure survey (CES). We focus on finding adequate specification for modeling the demographic characteristics using parametric, nonparametric, and semiparametric techniques. The empirical results indicate parametric Working-Leser or Piglog specification was sufficient for most budget shares except for transportation where semiparametric specification had support.
Tipo: Conference Paper or Presentation Palavras-chave: Consumer/Household Economics.
Ano: 2006 URL: http://purl.umn.edu/21092
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BOOTSTRAPPING IN VECTOR AUTOREGRESSIONS: AN APPLICATION TO THE PORK SECTOR AgEcon
Susanto, Dwi; Zapata, Hector O.; Cramer, Gail L..
Standard bootstrap method is used to generate confidence intervals (CIs) of impulse response functions of VAR and SVAR models in the pork sector. In the VAR model, the bootstrap method does not produce significant different results from Monte Carlo simulations. In the SVAR analysis, on the other hand, the bootstrap CIs are significantly different from Monte Carlo CIs after a six period forecast intervals. This suggests that the choice of method used to measure reliability of IRFs is not trivial. Furthermore, bootstrap CIs in SVAR model seem to be more stable than MC CIs, which tend to be wider in the longer horizons.
Tipo: Conference Paper or Presentation Palavras-chave: Research Methods/ Statistical Methods.
Ano: 2004 URL: http://purl.umn.edu/20051
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LONG-RUN TREND ANALYSIS OF COUNTER-CYCLE PROGRAM COMMODITY PRICES IN THE FARM SECURITY AND RURAL DEVELOPMENT ACT OF 2002 AgEcon
No, Sung Chul; Salassi, Michael E.; Zapata, Hector O..
This study provides empirical evidence on whether corn, sorghum, oat, barley, wheat, rice, soybeans, cotton, and peanuts exhibit cyclical patterns in their historical prices. The results of time-series analysis support a newly added counter-cyclical payment in the Farm Security and Rural Investment Act of 2002 for all crops except corn.
Tipo: Conference Paper or Presentation Palavras-chave: Demand and Price Analysis.
Ano: 2003 URL: http://purl.umn.edu/35087
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Price Discovery in the World Sugar Futures and Cash Markets: Implications for the Dominican Republic AgEcon
Zapata, Hector O.; Fortenbery, T. Randall; Armstrong, Delroy.
This paper examines the relationship between #11 sugar futures prices traded in New York and the world cash prices for exported sugar. It was found that the futures market for sugar leads the cash market in price discovery. However, we fail to find evidence that changes in the cash price causes changes in futures price, that is, causality is unidirectional from futures to cash. The finding of cointegration between futures and cash prices suggests that the sugar futures contract is a useful vehicle for reducing overall market price risk faced by cash market participants selling at the world price (i.e., not enjoying favorable trade incentives). Further reliability on the usefulness of the WSF as a price discovery market is found through the impulse response...
Tipo: Working or Discussion Paper Palavras-chave: Industrial Organization.
Ano: 2005 URL: http://purl.umn.edu/12657
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MONTE CARLO EVIDENCE ON COINTEGRATION AND CAUSATION AgEcon
Zapata, Hector O.; Rambaldi, Alicia N..
The small sample performance of Granger causality tests under different model dimensions, degree of cointegration, direction of causality, and system stability are presented. Two tests based on maximum likelihood estimation of error-correction models (LR and WALD) are compared to a Wald test based on multivariate least squares estimation of a modified VAR (MWALD). In large samples all test statistics perform well in terms of size and power. For smaller samples, the LR and WALD tests perform better than the MWALD test. Overall, the LR test outperforms the other two in terms of size and power in small samples.
Tipo: Working or Discussion Paper Palavras-chave: Causality tests; Cointegration; Likelihood ratio; Wald statistic; Monte Carlo Experiments; Research Methods/ Statistical Methods.
Ano: 1996 URL: http://purl.umn.edu/31690
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Mixed Unit Roots and Deterministic Trends in Noncausality Tests AgEcon
Ran, Tao; Zapata, Hector O..
Using Japanese economic data and a Monte Carlo simulation, this study analyzes the consequences of ignoring deterministic trends in mixed unit-root data for Granger noncausality tests. Results from an augmented VAR suggest over-rejection in certain empirically relevant cases at various sample sizes.
Tipo: Conference Paper or Presentation Palavras-chave: Research Methods/ Statistical Methods.
Ano: 2008 URL: http://purl.umn.edu/6745
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Use of Seemingly Unrelated Parametric and Semiparametric Panel Models in the Environmental Kuznets Curve Estimation AgEcon
Zapata, Hector O.; Paudel, Krishna P..
We estimated the environmental Kuznets curve for point (mercury) and nonpoint (nitrogen, phosphorus, and dissolved oxygen) source water pollutants as a function of income in parametric and semiparametric functional forms of the Panel data model. Seemingly unrelated panel formulation did not provide gain in efficiency over the single equation panel data model.
Tipo: Conference Paper or Presentation Palavras-chave: Environmental Economics and Policy.
Ano: 2005 URL: http://purl.umn.edu/35495
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Noncompetitive Pricing and Exchange Rate Pass-Through in Mauritanian Octopus Export Markets AgEcon
Kazmierczak, Richard F., Jr.; Zapata, Hector O.; Diop, Hamady.
Octopus exports are an important source of foreign exchange for Mauritania. The export market has historically been dominated by coordinated Japanese buyers, a situation that led Mauritania to create the Societe Mauritanienne de Commercialisation de Poisson (SMCP) to negotiate with buyers and manage all octopus exports. Issues concerning competitiveness, price discrimination, and exchange rate pass-through in the Mauritanian octopus export market corrected for contemporaneous and serial correlation. Results indicate some degree of price discrimination across destination markets, market share enhancement through local currency price stabilization, and increases in marginal costs of production following nationalization of the Mauritanian trawler fleet. Thus,...
Tipo: Journal Article Palavras-chave: International trade; Exchange rates; Imperfect competition; Octopus fisheries; Agribusiness; Demand and Price Analysis; International Relations/Trade.
Ano: 1997 URL: http://purl.umn.edu/90407
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IDENTIFYING CAUSAL RELATIONSHIPS BETWEEN NONSTATIONARY STOCHASTIC PROCESSES: AN EXAMINATION OF ALTERNATIVE APPROACHES IN SMALL SAMPLES AgEcon
Zapata, Hector O.; Hudson, Michael A.; Garcia, Philip.
A Monte Carlo investigation is used to examine the performance of two commonly used tests for Granger causality for univariate and bivariate nonstationary ARMA (p,q) processes. Tests are applied to raw data, first differences of the raw data, and detrended versions of the series. The results indicate that for independent series the tests are robust regardless of sample size. With bivariate series and nonstationarity, the tests results are sensitive to the ARMA specification, whether the data are filtered and the type of filter used, and the sample size.
Tipo: Journal Article Palavras-chave: Research Methods/ Statistical Methods.
Ano: 1988 URL: http://purl.umn.edu/32108
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Carbon Dioxide (CO2) Emissions in Latin America: Looking for the Existence of Environmental Kuznets Curves AgEcon
Paudel, Krishna P.; Zapata, Hector O.; Diaz, Alehandro; Bhattarai, Keshav.
We estimated environmental Kuznets curve (EKC) for carbon dioxide for 16 Latin American countries using nonparametric, semi-parametric, and parametric specifications. Results indicated that most of the Latin American countries are still in the rising portion of the EKC with respect to CO2 pollution.
Tipo: Conference Paper or Presentation Palavras-chave: Environmental Economics and Policy.
Ano: 2005 URL: http://purl.umn.edu/35619
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THRESHOLD MODELS IN THEORY AND PRACTICE AgEcon
Zapata, Hector O.; Gauthier, Wayne M..
Threshold models have gained much recent attention in applied economics for modeling nonlinear behavior. The appeal for these models is due in part to the observable pattern that many economic variables follow, such as asymmetric adjustment towards equilibrium. This paper reviews the literature and provides links to software programs.
Tipo: Conference Paper or Presentation Palavras-chave: Research Methods/ Statistical Methods.
Ano: 2003 URL: http://purl.umn.edu/35147
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Choice Models in Policy Analysis AgEcon
Zapata, Hector O.; Sambidi, Pramod R.; Dufour, Elizabeth Anne.
The survey article provides a selected review of studies on econometric choice modeling of different agricultural policy issues. The study discusses how one model is preferred over the other and in what circumstances a particular model should be used.
Tipo: Conference Paper or Presentation Palavras-chave: Agricultural and Food Policy.
Ano: 2007 URL: http://purl.umn.edu/34810
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Recent Developments in Unit Root Tests and Historical Crop Yields AgEcon
Zapata, Hector O.; Maradiaga, David Isaias; Pujula, Aude Liliana; Dicks, Michael R..
This study conducts an investigation on the application of classical unit-root tests using parametric tests (the augmented Dickey-Fuller, 1979 – ADF), and nonparametric tests (Phillips and Perron, 1988—PP) to corn and soybean yields in the Delta states using county-level data from 1961 to 2009. The main concern of the paper is to assess what would be drawn about nonstationarity in crop yields using these tests versus using modified versions of these tests (Ng and Perron, 2001) that are assumed to solve size and power problems associated with the ADF and PP tests. The investigation focuses on methodological aspects of the classical tests, uncovers the nature of filtered yields often needed prior to density estimation, sheds light on the effect of lag...
Tipo: Conference Paper or Presentation Palavras-chave: Crop yields; Nonstationarity; Unit-roots; Density estimation; Production Economics; Research Methods/ Statistical Methods; Risk and Uncertainty.
Ano: 2011 URL: http://purl.umn.edu/103871
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TWO METHODS OF ESTIMATING SEMIPARAMETRIC COMPONENT IN THE ENVIRONMENTAL KUZNET'S CURVE (EKC) AgEcon
Paudel, Krishna P.; Zapata, Hector O..
This study compares parametric and semiparametric smoothing techniques to estimate the environmental Kuznet curve. The ad hoc functional form where income is related either as a square or a cubic function to environmental quality is relaxed in search of a better nonlinear fit to the pollution-income relationship for panel data.
Tipo: Conference Paper or Presentation Palavras-chave: Environmental Economics and Policy.
Ano: 2004 URL: http://purl.umn.edu/34598
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A DYNAMIC RESPONSE ANALYSIS FOR THE U.S. ROUGH RICE MARKET AgEcon
No, Sung Chul; Zapata, Hector O..
This study provides a comparative evaluation of VARs versus structural VARs for policy analysis and simulation via impulse response analysis (IRA). The IRA is valuable information for rice market participants as these results provide an economically intuitive explanation of adjustments that occur as a result of shocks to the market.
Tipo: Conference Paper or Presentation Palavras-chave: Marketing.
Ano: 2001 URL: http://purl.umn.edu/20765
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STOCHASTIC INTEREST RATES AND PRICE DISCOVERY IN SELECTED COMMODITY MARKETS AgEcon
Zapata, Hector O.; Fortenbery, T. Randall.
The temporal relationship between Chicago corn and soybean cash prices, nearby futures prices, and interest rates is examined using daily 1980-1989 data. Johansen cointegration tests suggest joint movement of the three series over the data period considered. In addition, analyses of individual crop years, which is consistent with previous work, shows co-movement between cash, futures, and interest rates in years when bivariate cointegration between cash and futures prices was not found. The results provide initial empirical evidence that a potential limitation of previous research in the study of cash- futures simple efficiency has been the exclusion of the interest rate as a common stochastic factor explaining equilibrium in models of cash and futures...
Tipo: Working or Discussion Paper Palavras-chave: Demand and Price Analysis.
Ano: 1995 URL: http://purl.umn.edu/12637
Registros recuperados: 31
Primeira ... 12 ... Última
 

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